![Eric W. Biederman](/assets/img/avatar_default.png)
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1438 lines
37 KiB
C
1438 lines
37 KiB
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (c) 2004-2006 Silicon Graphics, Inc. All Rights Reserved.
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*/
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/*
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* Cross Partition Communication (XPC) support - standard version.
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*
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* XPC provides a message passing capability that crosses partition
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* boundaries. This module is made up of two parts:
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*
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* partition This part detects the presence/absence of other
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* partitions. It provides a heartbeat and monitors
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* the heartbeats of other partitions.
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*
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* channel This part manages the channels and sends/receives
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* messages across them to/from other partitions.
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*
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* There are a couple of additional functions residing in XP, which
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* provide an interface to XPC for its users.
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*
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*
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* Caveats:
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*
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* . We currently have no way to determine which nasid an IPI came
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* from. Thus, xpc_IPI_send() does a remote AMO write followed by
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* an IPI. The AMO indicates where data is to be pulled from, so
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* after the IPI arrives, the remote partition checks the AMO word.
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* The IPI can actually arrive before the AMO however, so other code
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* must periodically check for this case. Also, remote AMO operations
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* do not reliably time out. Thus we do a remote PIO read solely to
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* know whether the remote partition is down and whether we should
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* stop sending IPIs to it. This remote PIO read operation is set up
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* in a special nofault region so SAL knows to ignore (and cleanup)
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* any errors due to the remote AMO write, PIO read, and/or PIO
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* write operations.
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*
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* If/when new hardware solves this IPI problem, we should abandon
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* the current approach.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/syscalls.h>
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#include <linux/cache.h>
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#include <linux/interrupt.h>
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#include <linux/delay.h>
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#include <linux/reboot.h>
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#include <linux/completion.h>
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#include <asm/sn/intr.h>
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#include <asm/sn/sn_sal.h>
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#include <asm/kdebug.h>
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#include <asm/uaccess.h>
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#include <asm/sn/xpc.h>
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/* define two XPC debug device structures to be used with dev_dbg() et al */
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struct device_driver xpc_dbg_name = {
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.name = "xpc"
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};
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struct device xpc_part_dbg_subname = {
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.bus_id = {0}, /* set to "part" at xpc_init() time */
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.driver = &xpc_dbg_name
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};
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struct device xpc_chan_dbg_subname = {
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.bus_id = {0}, /* set to "chan" at xpc_init() time */
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.driver = &xpc_dbg_name
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};
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struct device *xpc_part = &xpc_part_dbg_subname;
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struct device *xpc_chan = &xpc_chan_dbg_subname;
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static int xpc_kdebug_ignore;
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/* systune related variables for /proc/sys directories */
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static int xpc_hb_interval = XPC_HB_DEFAULT_INTERVAL;
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static int xpc_hb_min_interval = 1;
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static int xpc_hb_max_interval = 10;
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static int xpc_hb_check_interval = XPC_HB_CHECK_DEFAULT_INTERVAL;
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static int xpc_hb_check_min_interval = 10;
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static int xpc_hb_check_max_interval = 120;
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int xpc_disengage_request_timelimit = XPC_DISENGAGE_REQUEST_DEFAULT_TIMELIMIT;
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static int xpc_disengage_request_min_timelimit = 0;
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static int xpc_disengage_request_max_timelimit = 120;
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static ctl_table xpc_sys_xpc_hb_dir[] = {
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{
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.ctl_name = CTL_UNNUMBERED,
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.procname = "hb_interval",
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.data = &xpc_hb_interval,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = &proc_dointvec_minmax,
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.strategy = &sysctl_intvec,
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.extra1 = &xpc_hb_min_interval,
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.extra2 = &xpc_hb_max_interval
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},
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{
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.ctl_name = CTL_UNNUMBERED,
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.procname = "hb_check_interval",
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.data = &xpc_hb_check_interval,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = &proc_dointvec_minmax,
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.strategy = &sysctl_intvec,
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.extra1 = &xpc_hb_check_min_interval,
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.extra2 = &xpc_hb_check_max_interval
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},
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{}
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};
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static ctl_table xpc_sys_xpc_dir[] = {
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{
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.ctl_name = CTL_UNNUMBERED,
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.procname = "hb",
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.mode = 0555,
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.child = xpc_sys_xpc_hb_dir
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},
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{
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.ctl_name = CTL_UNNUMBERED,
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.procname = "disengage_request_timelimit",
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.data = &xpc_disengage_request_timelimit,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = &proc_dointvec_minmax,
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.strategy = &sysctl_intvec,
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.extra1 = &xpc_disengage_request_min_timelimit,
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.extra2 = &xpc_disengage_request_max_timelimit
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},
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{}
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};
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static ctl_table xpc_sys_dir[] = {
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{
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.ctl_name = CTL_UNNUMBERED,
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.procname = "xpc",
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.mode = 0555,
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.child = xpc_sys_xpc_dir
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},
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{}
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};
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static struct ctl_table_header *xpc_sysctl;
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/* non-zero if any remote partition disengage request was timed out */
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int xpc_disengage_request_timedout;
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/* #of IRQs received */
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static atomic_t xpc_act_IRQ_rcvd;
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/* IRQ handler notifies this wait queue on receipt of an IRQ */
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static DECLARE_WAIT_QUEUE_HEAD(xpc_act_IRQ_wq);
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static unsigned long xpc_hb_check_timeout;
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/* notification that the xpc_hb_checker thread has exited */
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static DECLARE_COMPLETION(xpc_hb_checker_exited);
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/* notification that the xpc_discovery thread has exited */
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static DECLARE_COMPLETION(xpc_discovery_exited);
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static struct timer_list xpc_hb_timer;
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static void xpc_kthread_waitmsgs(struct xpc_partition *, struct xpc_channel *);
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static int xpc_system_reboot(struct notifier_block *, unsigned long, void *);
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static struct notifier_block xpc_reboot_notifier = {
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.notifier_call = xpc_system_reboot,
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};
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static int xpc_system_die(struct notifier_block *, unsigned long, void *);
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static struct notifier_block xpc_die_notifier = {
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.notifier_call = xpc_system_die,
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};
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/*
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* Timer function to enforce the timelimit on the partition disengage request.
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*/
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static void
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xpc_timeout_partition_disengage_request(unsigned long data)
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{
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struct xpc_partition *part = (struct xpc_partition *) data;
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DBUG_ON(jiffies < part->disengage_request_timeout);
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(void) xpc_partition_disengaged(part);
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DBUG_ON(part->disengage_request_timeout != 0);
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DBUG_ON(xpc_partition_engaged(1UL << XPC_PARTID(part)) != 0);
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}
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/*
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* Notify the heartbeat check thread that an IRQ has been received.
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*/
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static irqreturn_t
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xpc_act_IRQ_handler(int irq, void *dev_id)
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{
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atomic_inc(&xpc_act_IRQ_rcvd);
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wake_up_interruptible(&xpc_act_IRQ_wq);
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return IRQ_HANDLED;
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}
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/*
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* Timer to produce the heartbeat. The timer structures function is
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* already set when this is initially called. A tunable is used to
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* specify when the next timeout should occur.
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*/
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static void
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xpc_hb_beater(unsigned long dummy)
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{
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xpc_vars->heartbeat++;
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if (jiffies >= xpc_hb_check_timeout) {
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wake_up_interruptible(&xpc_act_IRQ_wq);
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}
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xpc_hb_timer.expires = jiffies + (xpc_hb_interval * HZ);
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add_timer(&xpc_hb_timer);
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}
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/*
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* This thread is responsible for nearly all of the partition
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* activation/deactivation.
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*/
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static int
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xpc_hb_checker(void *ignore)
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{
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int last_IRQ_count = 0;
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int new_IRQ_count;
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int force_IRQ=0;
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/* this thread was marked active by xpc_hb_init() */
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daemonize(XPC_HB_CHECK_THREAD_NAME);
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set_cpus_allowed(current, cpumask_of_cpu(XPC_HB_CHECK_CPU));
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xpc_hb_check_timeout = jiffies + (xpc_hb_check_interval * HZ);
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while (!(volatile int) xpc_exiting) {
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dev_dbg(xpc_part, "woke up with %d ticks rem; %d IRQs have "
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"been received\n",
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(int) (xpc_hb_check_timeout - jiffies),
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atomic_read(&xpc_act_IRQ_rcvd) - last_IRQ_count);
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/* checking of remote heartbeats is skewed by IRQ handling */
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if (jiffies >= xpc_hb_check_timeout) {
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dev_dbg(xpc_part, "checking remote heartbeats\n");
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xpc_check_remote_hb();
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/*
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* We need to periodically recheck to ensure no
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* IPI/AMO pairs have been missed. That check
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* must always reset xpc_hb_check_timeout.
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*/
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force_IRQ = 1;
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}
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/* check for outstanding IRQs */
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new_IRQ_count = atomic_read(&xpc_act_IRQ_rcvd);
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if (last_IRQ_count < new_IRQ_count || force_IRQ != 0) {
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force_IRQ = 0;
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dev_dbg(xpc_part, "found an IRQ to process; will be "
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"resetting xpc_hb_check_timeout\n");
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last_IRQ_count += xpc_identify_act_IRQ_sender();
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if (last_IRQ_count < new_IRQ_count) {
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/* retry once to help avoid missing AMO */
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(void) xpc_identify_act_IRQ_sender();
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}
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last_IRQ_count = new_IRQ_count;
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xpc_hb_check_timeout = jiffies +
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(xpc_hb_check_interval * HZ);
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}
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/* wait for IRQ or timeout */
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(void) wait_event_interruptible(xpc_act_IRQ_wq,
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(last_IRQ_count < atomic_read(&xpc_act_IRQ_rcvd) ||
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jiffies >= xpc_hb_check_timeout ||
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(volatile int) xpc_exiting));
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}
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dev_dbg(xpc_part, "heartbeat checker is exiting\n");
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/* mark this thread as having exited */
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complete(&xpc_hb_checker_exited);
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return 0;
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}
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/*
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* This thread will attempt to discover other partitions to activate
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* based on info provided by SAL. This new thread is short lived and
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* will exit once discovery is complete.
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*/
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static int
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xpc_initiate_discovery(void *ignore)
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{
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daemonize(XPC_DISCOVERY_THREAD_NAME);
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xpc_discovery();
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dev_dbg(xpc_part, "discovery thread is exiting\n");
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/* mark this thread as having exited */
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complete(&xpc_discovery_exited);
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return 0;
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}
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/*
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* Establish first contact with the remote partititon. This involves pulling
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* the XPC per partition variables from the remote partition and waiting for
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* the remote partition to pull ours.
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*/
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static enum xpc_retval
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xpc_make_first_contact(struct xpc_partition *part)
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{
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enum xpc_retval ret;
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while ((ret = xpc_pull_remote_vars_part(part)) != xpcSuccess) {
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if (ret != xpcRetry) {
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XPC_DEACTIVATE_PARTITION(part, ret);
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return ret;
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}
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dev_dbg(xpc_chan, "waiting to make first contact with "
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"partition %d\n", XPC_PARTID(part));
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/* wait a 1/4 of a second or so */
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(void) msleep_interruptible(250);
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if (part->act_state == XPC_P_DEACTIVATING) {
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return part->reason;
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}
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}
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return xpc_mark_partition_active(part);
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}
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/*
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* The first kthread assigned to a newly activated partition is the one
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* created by XPC HB with which it calls xpc_partition_up(). XPC hangs on to
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* that kthread until the partition is brought down, at which time that kthread
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* returns back to XPC HB. (The return of that kthread will signify to XPC HB
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* that XPC has dismantled all communication infrastructure for the associated
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* partition.) This kthread becomes the channel manager for that partition.
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*
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* Each active partition has a channel manager, who, besides connecting and
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* disconnecting channels, will ensure that each of the partition's connected
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* channels has the required number of assigned kthreads to get the work done.
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*/
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static void
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xpc_channel_mgr(struct xpc_partition *part)
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{
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while (part->act_state != XPC_P_DEACTIVATING ||
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atomic_read(&part->nchannels_active) > 0 ||
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!xpc_partition_disengaged(part)) {
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xpc_process_channel_activity(part);
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/*
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* Wait until we've been requested to activate kthreads or
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* all of the channel's message queues have been torn down or
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* a signal is pending.
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*
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* The channel_mgr_requests is set to 1 after being awakened,
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* This is done to prevent the channel mgr from making one pass
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* through the loop for each request, since he will
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* be servicing all the requests in one pass. The reason it's
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* set to 1 instead of 0 is so that other kthreads will know
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* that the channel mgr is running and won't bother trying to
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* wake him up.
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*/
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atomic_dec(&part->channel_mgr_requests);
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(void) wait_event_interruptible(part->channel_mgr_wq,
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(atomic_read(&part->channel_mgr_requests) > 0 ||
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(volatile u64) part->local_IPI_amo != 0 ||
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((volatile u8) part->act_state ==
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XPC_P_DEACTIVATING &&
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atomic_read(&part->nchannels_active) == 0 &&
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xpc_partition_disengaged(part))));
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atomic_set(&part->channel_mgr_requests, 1);
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// >>> Does it need to wakeup periodically as well? In case we
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// >>> miscalculated the #of kthreads to wakeup or create?
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}
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}
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/*
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* When XPC HB determines that a partition has come up, it will create a new
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* kthread and that kthread will call this function to attempt to set up the
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* basic infrastructure used for Cross Partition Communication with the newly
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* upped partition.
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*
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* The kthread that was created by XPC HB and which setup the XPC
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* infrastructure will remain assigned to the partition until the partition
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* goes down. At which time the kthread will teardown the XPC infrastructure
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* and then exit.
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*
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* XPC HB will put the remote partition's XPC per partition specific variables
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* physical address into xpc_partitions[partid].remote_vars_part_pa prior to
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* calling xpc_partition_up().
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*/
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static void
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xpc_partition_up(struct xpc_partition *part)
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{
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DBUG_ON(part->channels != NULL);
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dev_dbg(xpc_chan, "activating partition %d\n", XPC_PARTID(part));
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if (xpc_setup_infrastructure(part) != xpcSuccess) {
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return;
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}
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/*
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* The kthread that XPC HB called us with will become the
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* channel manager for this partition. It will not return
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* back to XPC HB until the partition's XPC infrastructure
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* has been dismantled.
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*/
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(void) xpc_part_ref(part); /* this will always succeed */
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if (xpc_make_first_contact(part) == xpcSuccess) {
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xpc_channel_mgr(part);
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}
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xpc_part_deref(part);
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xpc_teardown_infrastructure(part);
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}
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static int
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xpc_activating(void *__partid)
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{
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partid_t partid = (u64) __partid;
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struct xpc_partition *part = &xpc_partitions[partid];
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unsigned long irq_flags;
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struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
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int ret;
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DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
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spin_lock_irqsave(&part->act_lock, irq_flags);
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if (part->act_state == XPC_P_DEACTIVATING) {
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part->act_state = XPC_P_INACTIVE;
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spin_unlock_irqrestore(&part->act_lock, irq_flags);
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part->remote_rp_pa = 0;
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return 0;
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}
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/* indicate the thread is activating */
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DBUG_ON(part->act_state != XPC_P_ACTIVATION_REQ);
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part->act_state = XPC_P_ACTIVATING;
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XPC_SET_REASON(part, 0, 0);
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spin_unlock_irqrestore(&part->act_lock, irq_flags);
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dev_dbg(xpc_part, "bringing partition %d up\n", partid);
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daemonize("xpc%02d", partid);
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/*
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* This thread needs to run at a realtime priority to prevent a
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* significant performance degradation.
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*/
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ret = sched_setscheduler(current, SCHED_FIFO, ¶m);
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if (ret != 0) {
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dev_warn(xpc_part, "unable to set pid %d to a realtime "
|
|
"priority, ret=%d\n", current->pid, ret);
|
|
}
|
|
|
|
/* allow this thread and its children to run on any CPU */
|
|
set_cpus_allowed(current, CPU_MASK_ALL);
|
|
|
|
/*
|
|
* Register the remote partition's AMOs with SAL so it can handle
|
|
* and cleanup errors within that address range should the remote
|
|
* partition go down. We don't unregister this range because it is
|
|
* difficult to tell when outstanding writes to the remote partition
|
|
* are finished and thus when it is safe to unregister. This should
|
|
* not result in wasted space in the SAL xp_addr_region table because
|
|
* we should get the same page for remote_amos_page_pa after module
|
|
* reloads and system reboots.
|
|
*/
|
|
if (sn_register_xp_addr_region(part->remote_amos_page_pa,
|
|
PAGE_SIZE, 1) < 0) {
|
|
dev_warn(xpc_part, "xpc_partition_up(%d) failed to register "
|
|
"xp_addr region\n", partid);
|
|
|
|
spin_lock_irqsave(&part->act_lock, irq_flags);
|
|
part->act_state = XPC_P_INACTIVE;
|
|
XPC_SET_REASON(part, xpcPhysAddrRegFailed, __LINE__);
|
|
spin_unlock_irqrestore(&part->act_lock, irq_flags);
|
|
part->remote_rp_pa = 0;
|
|
return 0;
|
|
}
|
|
|
|
xpc_allow_hb(partid, xpc_vars);
|
|
xpc_IPI_send_activated(part);
|
|
|
|
|
|
/*
|
|
* xpc_partition_up() holds this thread and marks this partition as
|
|
* XPC_P_ACTIVE by calling xpc_hb_mark_active().
|
|
*/
|
|
(void) xpc_partition_up(part);
|
|
|
|
xpc_disallow_hb(partid, xpc_vars);
|
|
xpc_mark_partition_inactive(part);
|
|
|
|
if (part->reason == xpcReactivating) {
|
|
/* interrupting ourselves results in activating partition */
|
|
xpc_IPI_send_reactivate(part);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void
|
|
xpc_activate_partition(struct xpc_partition *part)
|
|
{
|
|
partid_t partid = XPC_PARTID(part);
|
|
unsigned long irq_flags;
|
|
pid_t pid;
|
|
|
|
|
|
spin_lock_irqsave(&part->act_lock, irq_flags);
|
|
|
|
DBUG_ON(part->act_state != XPC_P_INACTIVE);
|
|
|
|
part->act_state = XPC_P_ACTIVATION_REQ;
|
|
XPC_SET_REASON(part, xpcCloneKThread, __LINE__);
|
|
|
|
spin_unlock_irqrestore(&part->act_lock, irq_flags);
|
|
|
|
pid = kernel_thread(xpc_activating, (void *) ((u64) partid), 0);
|
|
|
|
if (unlikely(pid <= 0)) {
|
|
spin_lock_irqsave(&part->act_lock, irq_flags);
|
|
part->act_state = XPC_P_INACTIVE;
|
|
XPC_SET_REASON(part, xpcCloneKThreadFailed, __LINE__);
|
|
spin_unlock_irqrestore(&part->act_lock, irq_flags);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Handle the receipt of a SGI_XPC_NOTIFY IRQ by seeing whether the specified
|
|
* partition actually sent it. Since SGI_XPC_NOTIFY IRQs may be shared by more
|
|
* than one partition, we use an AMO_t structure per partition to indicate
|
|
* whether a partition has sent an IPI or not. >>> If it has, then wake up the
|
|
* associated kthread to handle it.
|
|
*
|
|
* All SGI_XPC_NOTIFY IRQs received by XPC are the result of IPIs sent by XPC
|
|
* running on other partitions.
|
|
*
|
|
* Noteworthy Arguments:
|
|
*
|
|
* irq - Interrupt ReQuest number. NOT USED.
|
|
*
|
|
* dev_id - partid of IPI's potential sender.
|
|
*/
|
|
irqreturn_t
|
|
xpc_notify_IRQ_handler(int irq, void *dev_id)
|
|
{
|
|
partid_t partid = (partid_t) (u64) dev_id;
|
|
struct xpc_partition *part = &xpc_partitions[partid];
|
|
|
|
|
|
DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
|
|
|
|
if (xpc_part_ref(part)) {
|
|
xpc_check_for_channel_activity(part);
|
|
|
|
xpc_part_deref(part);
|
|
}
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
|
|
/*
|
|
* Check to see if xpc_notify_IRQ_handler() dropped any IPIs on the floor
|
|
* because the write to their associated IPI amo completed after the IRQ/IPI
|
|
* was received.
|
|
*/
|
|
void
|
|
xpc_dropped_IPI_check(struct xpc_partition *part)
|
|
{
|
|
if (xpc_part_ref(part)) {
|
|
xpc_check_for_channel_activity(part);
|
|
|
|
part->dropped_IPI_timer.expires = jiffies +
|
|
XPC_P_DROPPED_IPI_WAIT;
|
|
add_timer(&part->dropped_IPI_timer);
|
|
xpc_part_deref(part);
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
xpc_activate_kthreads(struct xpc_channel *ch, int needed)
|
|
{
|
|
int idle = atomic_read(&ch->kthreads_idle);
|
|
int assigned = atomic_read(&ch->kthreads_assigned);
|
|
int wakeup;
|
|
|
|
|
|
DBUG_ON(needed <= 0);
|
|
|
|
if (idle > 0) {
|
|
wakeup = (needed > idle) ? idle : needed;
|
|
needed -= wakeup;
|
|
|
|
dev_dbg(xpc_chan, "wakeup %d idle kthreads, partid=%d, "
|
|
"channel=%d\n", wakeup, ch->partid, ch->number);
|
|
|
|
/* only wakeup the requested number of kthreads */
|
|
wake_up_nr(&ch->idle_wq, wakeup);
|
|
}
|
|
|
|
if (needed <= 0) {
|
|
return;
|
|
}
|
|
|
|
if (needed + assigned > ch->kthreads_assigned_limit) {
|
|
needed = ch->kthreads_assigned_limit - assigned;
|
|
// >>>should never be less than 0
|
|
if (needed <= 0) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
dev_dbg(xpc_chan, "create %d new kthreads, partid=%d, channel=%d\n",
|
|
needed, ch->partid, ch->number);
|
|
|
|
xpc_create_kthreads(ch, needed, 0);
|
|
}
|
|
|
|
|
|
/*
|
|
* This function is where XPC's kthreads wait for messages to deliver.
|
|
*/
|
|
static void
|
|
xpc_kthread_waitmsgs(struct xpc_partition *part, struct xpc_channel *ch)
|
|
{
|
|
do {
|
|
/* deliver messages to their intended recipients */
|
|
|
|
while ((volatile s64) ch->w_local_GP.get <
|
|
(volatile s64) ch->w_remote_GP.put &&
|
|
!((volatile u32) ch->flags &
|
|
XPC_C_DISCONNECTING)) {
|
|
xpc_deliver_msg(ch);
|
|
}
|
|
|
|
if (atomic_inc_return(&ch->kthreads_idle) >
|
|
ch->kthreads_idle_limit) {
|
|
/* too many idle kthreads on this channel */
|
|
atomic_dec(&ch->kthreads_idle);
|
|
break;
|
|
}
|
|
|
|
dev_dbg(xpc_chan, "idle kthread calling "
|
|
"wait_event_interruptible_exclusive()\n");
|
|
|
|
(void) wait_event_interruptible_exclusive(ch->idle_wq,
|
|
((volatile s64) ch->w_local_GP.get <
|
|
(volatile s64) ch->w_remote_GP.put ||
|
|
((volatile u32) ch->flags &
|
|
XPC_C_DISCONNECTING)));
|
|
|
|
atomic_dec(&ch->kthreads_idle);
|
|
|
|
} while (!((volatile u32) ch->flags & XPC_C_DISCONNECTING));
|
|
}
|
|
|
|
|
|
static int
|
|
xpc_daemonize_kthread(void *args)
|
|
{
|
|
partid_t partid = XPC_UNPACK_ARG1(args);
|
|
u16 ch_number = XPC_UNPACK_ARG2(args);
|
|
struct xpc_partition *part = &xpc_partitions[partid];
|
|
struct xpc_channel *ch;
|
|
int n_needed;
|
|
unsigned long irq_flags;
|
|
|
|
|
|
daemonize("xpc%02dc%d", partid, ch_number);
|
|
|
|
dev_dbg(xpc_chan, "kthread starting, partid=%d, channel=%d\n",
|
|
partid, ch_number);
|
|
|
|
ch = &part->channels[ch_number];
|
|
|
|
if (!(ch->flags & XPC_C_DISCONNECTING)) {
|
|
|
|
/* let registerer know that connection has been established */
|
|
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
if (!(ch->flags & XPC_C_CONNECTEDCALLOUT)) {
|
|
ch->flags |= XPC_C_CONNECTEDCALLOUT;
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
|
|
xpc_connected_callout(ch);
|
|
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
ch->flags |= XPC_C_CONNECTEDCALLOUT_MADE;
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
|
|
/*
|
|
* It is possible that while the callout was being
|
|
* made that the remote partition sent some messages.
|
|
* If that is the case, we may need to activate
|
|
* additional kthreads to help deliver them. We only
|
|
* need one less than total #of messages to deliver.
|
|
*/
|
|
n_needed = ch->w_remote_GP.put - ch->w_local_GP.get - 1;
|
|
if (n_needed > 0 &&
|
|
!(ch->flags & XPC_C_DISCONNECTING)) {
|
|
xpc_activate_kthreads(ch, n_needed);
|
|
}
|
|
} else {
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
}
|
|
|
|
xpc_kthread_waitmsgs(part, ch);
|
|
}
|
|
|
|
/* let registerer know that connection is disconnecting */
|
|
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
if ((ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) &&
|
|
!(ch->flags & XPC_C_DISCONNECTINGCALLOUT)) {
|
|
ch->flags |= XPC_C_DISCONNECTINGCALLOUT;
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
|
|
xpc_disconnect_callout(ch, xpcDisconnecting);
|
|
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
ch->flags |= XPC_C_DISCONNECTINGCALLOUT_MADE;
|
|
}
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
|
|
if (atomic_dec_return(&ch->kthreads_assigned) == 0) {
|
|
if (atomic_dec_return(&part->nchannels_engaged) == 0) {
|
|
xpc_mark_partition_disengaged(part);
|
|
xpc_IPI_send_disengage(part);
|
|
}
|
|
}
|
|
|
|
xpc_msgqueue_deref(ch);
|
|
|
|
dev_dbg(xpc_chan, "kthread exiting, partid=%d, channel=%d\n",
|
|
partid, ch_number);
|
|
|
|
xpc_part_deref(part);
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* For each partition that XPC has established communications with, there is
|
|
* a minimum of one kernel thread assigned to perform any operation that
|
|
* may potentially sleep or block (basically the callouts to the asynchronous
|
|
* functions registered via xpc_connect()).
|
|
*
|
|
* Additional kthreads are created and destroyed by XPC as the workload
|
|
* demands.
|
|
*
|
|
* A kthread is assigned to one of the active channels that exists for a given
|
|
* partition.
|
|
*/
|
|
void
|
|
xpc_create_kthreads(struct xpc_channel *ch, int needed,
|
|
int ignore_disconnecting)
|
|
{
|
|
unsigned long irq_flags;
|
|
pid_t pid;
|
|
u64 args = XPC_PACK_ARGS(ch->partid, ch->number);
|
|
struct xpc_partition *part = &xpc_partitions[ch->partid];
|
|
|
|
|
|
while (needed-- > 0) {
|
|
|
|
/*
|
|
* The following is done on behalf of the newly created
|
|
* kthread. That kthread is responsible for doing the
|
|
* counterpart to the following before it exits.
|
|
*/
|
|
if (ignore_disconnecting) {
|
|
if (!atomic_inc_not_zero(&ch->kthreads_assigned)) {
|
|
/* kthreads assigned had gone to zero */
|
|
BUG_ON(!(ch->flags &
|
|
XPC_C_DISCONNECTINGCALLOUT_MADE));
|
|
break;
|
|
}
|
|
|
|
} else if (ch->flags & XPC_C_DISCONNECTING) {
|
|
break;
|
|
|
|
} else if (atomic_inc_return(&ch->kthreads_assigned) == 1) {
|
|
if (atomic_inc_return(&part->nchannels_engaged) == 1)
|
|
xpc_mark_partition_engaged(part);
|
|
}
|
|
(void) xpc_part_ref(part);
|
|
xpc_msgqueue_ref(ch);
|
|
|
|
pid = kernel_thread(xpc_daemonize_kthread, (void *) args, 0);
|
|
if (pid < 0) {
|
|
/* the fork failed */
|
|
|
|
/*
|
|
* NOTE: if (ignore_disconnecting &&
|
|
* !(ch->flags & XPC_C_DISCONNECTINGCALLOUT)) is true,
|
|
* then we'll deadlock if all other kthreads assigned
|
|
* to this channel are blocked in the channel's
|
|
* registerer, because the only thing that will unblock
|
|
* them is the xpcDisconnecting callout that this
|
|
* failed kernel_thread would have made.
|
|
*/
|
|
|
|
if (atomic_dec_return(&ch->kthreads_assigned) == 0 &&
|
|
atomic_dec_return(&part->nchannels_engaged) == 0) {
|
|
xpc_mark_partition_disengaged(part);
|
|
xpc_IPI_send_disengage(part);
|
|
}
|
|
xpc_msgqueue_deref(ch);
|
|
xpc_part_deref(part);
|
|
|
|
if (atomic_read(&ch->kthreads_assigned) <
|
|
ch->kthreads_idle_limit) {
|
|
/*
|
|
* Flag this as an error only if we have an
|
|
* insufficient #of kthreads for the channel
|
|
* to function.
|
|
*/
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
XPC_DISCONNECT_CHANNEL(ch, xpcLackOfResources,
|
|
&irq_flags);
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
}
|
|
break;
|
|
}
|
|
|
|
ch->kthreads_created++; // >>> temporary debug only!!!
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
xpc_disconnect_wait(int ch_number)
|
|
{
|
|
unsigned long irq_flags;
|
|
partid_t partid;
|
|
struct xpc_partition *part;
|
|
struct xpc_channel *ch;
|
|
int wakeup_channel_mgr;
|
|
|
|
|
|
/* now wait for all callouts to the caller's function to cease */
|
|
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
|
|
part = &xpc_partitions[partid];
|
|
|
|
if (!xpc_part_ref(part)) {
|
|
continue;
|
|
}
|
|
|
|
ch = &part->channels[ch_number];
|
|
|
|
if (!(ch->flags & XPC_C_WDISCONNECT)) {
|
|
xpc_part_deref(part);
|
|
continue;
|
|
}
|
|
|
|
wait_for_completion(&ch->wdisconnect_wait);
|
|
|
|
spin_lock_irqsave(&ch->lock, irq_flags);
|
|
DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));
|
|
wakeup_channel_mgr = 0;
|
|
|
|
if (ch->delayed_IPI_flags) {
|
|
if (part->act_state != XPC_P_DEACTIVATING) {
|
|
spin_lock(&part->IPI_lock);
|
|
XPC_SET_IPI_FLAGS(part->local_IPI_amo,
|
|
ch->number, ch->delayed_IPI_flags);
|
|
spin_unlock(&part->IPI_lock);
|
|
wakeup_channel_mgr = 1;
|
|
}
|
|
ch->delayed_IPI_flags = 0;
|
|
}
|
|
|
|
ch->flags &= ~XPC_C_WDISCONNECT;
|
|
spin_unlock_irqrestore(&ch->lock, irq_flags);
|
|
|
|
if (wakeup_channel_mgr) {
|
|
xpc_wakeup_channel_mgr(part);
|
|
}
|
|
|
|
xpc_part_deref(part);
|
|
}
|
|
}
|
|
|
|
|
|
static void
|
|
xpc_do_exit(enum xpc_retval reason)
|
|
{
|
|
partid_t partid;
|
|
int active_part_count, printed_waiting_msg = 0;
|
|
struct xpc_partition *part;
|
|
unsigned long printmsg_time, disengage_request_timeout = 0;
|
|
|
|
|
|
/* a 'rmmod XPC' and a 'reboot' cannot both end up here together */
|
|
DBUG_ON(xpc_exiting == 1);
|
|
|
|
/*
|
|
* Let the heartbeat checker thread and the discovery thread
|
|
* (if one is running) know that they should exit. Also wake up
|
|
* the heartbeat checker thread in case it's sleeping.
|
|
*/
|
|
xpc_exiting = 1;
|
|
wake_up_interruptible(&xpc_act_IRQ_wq);
|
|
|
|
/* ignore all incoming interrupts */
|
|
free_irq(SGI_XPC_ACTIVATE, NULL);
|
|
|
|
/* wait for the discovery thread to exit */
|
|
wait_for_completion(&xpc_discovery_exited);
|
|
|
|
/* wait for the heartbeat checker thread to exit */
|
|
wait_for_completion(&xpc_hb_checker_exited);
|
|
|
|
|
|
/* sleep for a 1/3 of a second or so */
|
|
(void) msleep_interruptible(300);
|
|
|
|
|
|
/* wait for all partitions to become inactive */
|
|
|
|
printmsg_time = jiffies + (XPC_DISENGAGE_PRINTMSG_INTERVAL * HZ);
|
|
xpc_disengage_request_timedout = 0;
|
|
|
|
do {
|
|
active_part_count = 0;
|
|
|
|
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
|
|
part = &xpc_partitions[partid];
|
|
|
|
if (xpc_partition_disengaged(part) &&
|
|
part->act_state == XPC_P_INACTIVE) {
|
|
continue;
|
|
}
|
|
|
|
active_part_count++;
|
|
|
|
XPC_DEACTIVATE_PARTITION(part, reason);
|
|
|
|
if (part->disengage_request_timeout >
|
|
disengage_request_timeout) {
|
|
disengage_request_timeout =
|
|
part->disengage_request_timeout;
|
|
}
|
|
}
|
|
|
|
if (xpc_partition_engaged(-1UL)) {
|
|
if (time_after(jiffies, printmsg_time)) {
|
|
dev_info(xpc_part, "waiting for remote "
|
|
"partitions to disengage, timeout in "
|
|
"%ld seconds\n",
|
|
(disengage_request_timeout - jiffies)
|
|
/ HZ);
|
|
printmsg_time = jiffies +
|
|
(XPC_DISENGAGE_PRINTMSG_INTERVAL * HZ);
|
|
printed_waiting_msg = 1;
|
|
}
|
|
|
|
} else if (active_part_count > 0) {
|
|
if (printed_waiting_msg) {
|
|
dev_info(xpc_part, "waiting for local partition"
|
|
" to disengage\n");
|
|
printed_waiting_msg = 0;
|
|
}
|
|
|
|
} else {
|
|
if (!xpc_disengage_request_timedout) {
|
|
dev_info(xpc_part, "all partitions have "
|
|
"disengaged\n");
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* sleep for a 1/3 of a second or so */
|
|
(void) msleep_interruptible(300);
|
|
|
|
} while (1);
|
|
|
|
DBUG_ON(xpc_partition_engaged(-1UL));
|
|
|
|
|
|
/* indicate to others that our reserved page is uninitialized */
|
|
xpc_rsvd_page->vars_pa = 0;
|
|
|
|
/* now it's time to eliminate our heartbeat */
|
|
del_timer_sync(&xpc_hb_timer);
|
|
DBUG_ON(xpc_vars->heartbeating_to_mask != 0);
|
|
|
|
if (reason == xpcUnloading) {
|
|
/* take ourselves off of the reboot_notifier_list */
|
|
(void) unregister_reboot_notifier(&xpc_reboot_notifier);
|
|
|
|
/* take ourselves off of the die_notifier list */
|
|
(void) unregister_die_notifier(&xpc_die_notifier);
|
|
}
|
|
|
|
/* close down protections for IPI operations */
|
|
xpc_restrict_IPI_ops();
|
|
|
|
|
|
/* clear the interface to XPC's functions */
|
|
xpc_clear_interface();
|
|
|
|
if (xpc_sysctl) {
|
|
unregister_sysctl_table(xpc_sysctl);
|
|
}
|
|
|
|
kfree(xpc_remote_copy_buffer_base);
|
|
}
|
|
|
|
|
|
/*
|
|
* This function is called when the system is being rebooted.
|
|
*/
|
|
static int
|
|
xpc_system_reboot(struct notifier_block *nb, unsigned long event, void *unused)
|
|
{
|
|
enum xpc_retval reason;
|
|
|
|
|
|
switch (event) {
|
|
case SYS_RESTART:
|
|
reason = xpcSystemReboot;
|
|
break;
|
|
case SYS_HALT:
|
|
reason = xpcSystemHalt;
|
|
break;
|
|
case SYS_POWER_OFF:
|
|
reason = xpcSystemPoweroff;
|
|
break;
|
|
default:
|
|
reason = xpcSystemGoingDown;
|
|
}
|
|
|
|
xpc_do_exit(reason);
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
|
|
/*
|
|
* Notify other partitions to disengage from all references to our memory.
|
|
*/
|
|
static void
|
|
xpc_die_disengage(void)
|
|
{
|
|
struct xpc_partition *part;
|
|
partid_t partid;
|
|
unsigned long engaged;
|
|
long time, printmsg_time, disengage_request_timeout;
|
|
|
|
|
|
/* keep xpc_hb_checker thread from doing anything (just in case) */
|
|
xpc_exiting = 1;
|
|
|
|
xpc_vars->heartbeating_to_mask = 0; /* indicate we're deactivated */
|
|
|
|
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
|
|
part = &xpc_partitions[partid];
|
|
|
|
if (!XPC_SUPPORTS_DISENGAGE_REQUEST(part->
|
|
remote_vars_version)) {
|
|
|
|
/* just in case it was left set by an earlier XPC */
|
|
xpc_clear_partition_engaged(1UL << partid);
|
|
continue;
|
|
}
|
|
|
|
if (xpc_partition_engaged(1UL << partid) ||
|
|
part->act_state != XPC_P_INACTIVE) {
|
|
xpc_request_partition_disengage(part);
|
|
xpc_mark_partition_disengaged(part);
|
|
xpc_IPI_send_disengage(part);
|
|
}
|
|
}
|
|
|
|
time = rtc_time();
|
|
printmsg_time = time +
|
|
(XPC_DISENGAGE_PRINTMSG_INTERVAL * sn_rtc_cycles_per_second);
|
|
disengage_request_timeout = time +
|
|
(xpc_disengage_request_timelimit * sn_rtc_cycles_per_second);
|
|
|
|
/* wait for all other partitions to disengage from us */
|
|
|
|
while (1) {
|
|
engaged = xpc_partition_engaged(-1UL);
|
|
if (!engaged) {
|
|
dev_info(xpc_part, "all partitions have disengaged\n");
|
|
break;
|
|
}
|
|
|
|
time = rtc_time();
|
|
if (time >= disengage_request_timeout) {
|
|
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
|
|
if (engaged & (1UL << partid)) {
|
|
dev_info(xpc_part, "disengage from "
|
|
"remote partition %d timed "
|
|
"out\n", partid);
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (time >= printmsg_time) {
|
|
dev_info(xpc_part, "waiting for remote partitions to "
|
|
"disengage, timeout in %ld seconds\n",
|
|
(disengage_request_timeout - time) /
|
|
sn_rtc_cycles_per_second);
|
|
printmsg_time = time +
|
|
(XPC_DISENGAGE_PRINTMSG_INTERVAL *
|
|
sn_rtc_cycles_per_second);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* This function is called when the system is being restarted or halted due
|
|
* to some sort of system failure. If this is the case we need to notify the
|
|
* other partitions to disengage from all references to our memory.
|
|
* This function can also be called when our heartbeater could be offlined
|
|
* for a time. In this case we need to notify other partitions to not worry
|
|
* about the lack of a heartbeat.
|
|
*/
|
|
static int
|
|
xpc_system_die(struct notifier_block *nb, unsigned long event, void *unused)
|
|
{
|
|
switch (event) {
|
|
case DIE_MACHINE_RESTART:
|
|
case DIE_MACHINE_HALT:
|
|
xpc_die_disengage();
|
|
break;
|
|
|
|
case DIE_KDEBUG_ENTER:
|
|
/* Should lack of heartbeat be ignored by other partitions? */
|
|
if (!xpc_kdebug_ignore) {
|
|
break;
|
|
}
|
|
/* fall through */
|
|
case DIE_MCA_MONARCH_ENTER:
|
|
case DIE_INIT_MONARCH_ENTER:
|
|
xpc_vars->heartbeat++;
|
|
xpc_vars->heartbeat_offline = 1;
|
|
break;
|
|
|
|
case DIE_KDEBUG_LEAVE:
|
|
/* Is lack of heartbeat being ignored by other partitions? */
|
|
if (!xpc_kdebug_ignore) {
|
|
break;
|
|
}
|
|
/* fall through */
|
|
case DIE_MCA_MONARCH_LEAVE:
|
|
case DIE_INIT_MONARCH_LEAVE:
|
|
xpc_vars->heartbeat++;
|
|
xpc_vars->heartbeat_offline = 0;
|
|
break;
|
|
}
|
|
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
|
|
int __init
|
|
xpc_init(void)
|
|
{
|
|
int ret;
|
|
partid_t partid;
|
|
struct xpc_partition *part;
|
|
pid_t pid;
|
|
size_t buf_size;
|
|
|
|
|
|
if (!ia64_platform_is("sn2")) {
|
|
return -ENODEV;
|
|
}
|
|
|
|
|
|
buf_size = max(XPC_RP_VARS_SIZE,
|
|
XPC_RP_HEADER_SIZE + XP_NASID_MASK_BYTES);
|
|
xpc_remote_copy_buffer = xpc_kmalloc_cacheline_aligned(buf_size,
|
|
GFP_KERNEL, &xpc_remote_copy_buffer_base);
|
|
if (xpc_remote_copy_buffer == NULL)
|
|
return -ENOMEM;
|
|
|
|
snprintf(xpc_part->bus_id, BUS_ID_SIZE, "part");
|
|
snprintf(xpc_chan->bus_id, BUS_ID_SIZE, "chan");
|
|
|
|
xpc_sysctl = register_sysctl_table(xpc_sys_dir, 0);
|
|
|
|
/*
|
|
* The first few fields of each entry of xpc_partitions[] need to
|
|
* be initialized now so that calls to xpc_connect() and
|
|
* xpc_disconnect() can be made prior to the activation of any remote
|
|
* partition. NOTE THAT NONE OF THE OTHER FIELDS BELONGING TO THESE
|
|
* ENTRIES ARE MEANINGFUL UNTIL AFTER AN ENTRY'S CORRESPONDING
|
|
* PARTITION HAS BEEN ACTIVATED.
|
|
*/
|
|
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
|
|
part = &xpc_partitions[partid];
|
|
|
|
DBUG_ON((u64) part != L1_CACHE_ALIGN((u64) part));
|
|
|
|
part->act_IRQ_rcvd = 0;
|
|
spin_lock_init(&part->act_lock);
|
|
part->act_state = XPC_P_INACTIVE;
|
|
XPC_SET_REASON(part, 0, 0);
|
|
|
|
init_timer(&part->disengage_request_timer);
|
|
part->disengage_request_timer.function =
|
|
xpc_timeout_partition_disengage_request;
|
|
part->disengage_request_timer.data = (unsigned long) part;
|
|
|
|
part->setup_state = XPC_P_UNSET;
|
|
init_waitqueue_head(&part->teardown_wq);
|
|
atomic_set(&part->references, 0);
|
|
}
|
|
|
|
/*
|
|
* Open up protections for IPI operations (and AMO operations on
|
|
* Shub 1.1 systems).
|
|
*/
|
|
xpc_allow_IPI_ops();
|
|
|
|
/*
|
|
* Interrupts being processed will increment this atomic variable and
|
|
* awaken the heartbeat thread which will process the interrupts.
|
|
*/
|
|
atomic_set(&xpc_act_IRQ_rcvd, 0);
|
|
|
|
/*
|
|
* This is safe to do before the xpc_hb_checker thread has started
|
|
* because the handler releases a wait queue. If an interrupt is
|
|
* received before the thread is waiting, it will not go to sleep,
|
|
* but rather immediately process the interrupt.
|
|
*/
|
|
ret = request_irq(SGI_XPC_ACTIVATE, xpc_act_IRQ_handler, 0,
|
|
"xpc hb", NULL);
|
|
if (ret != 0) {
|
|
dev_err(xpc_part, "can't register ACTIVATE IRQ handler, "
|
|
"errno=%d\n", -ret);
|
|
|
|
xpc_restrict_IPI_ops();
|
|
|
|
if (xpc_sysctl) {
|
|
unregister_sysctl_table(xpc_sysctl);
|
|
}
|
|
|
|
kfree(xpc_remote_copy_buffer_base);
|
|
return -EBUSY;
|
|
}
|
|
|
|
/*
|
|
* Fill the partition reserved page with the information needed by
|
|
* other partitions to discover we are alive and establish initial
|
|
* communications.
|
|
*/
|
|
xpc_rsvd_page = xpc_rsvd_page_init();
|
|
if (xpc_rsvd_page == NULL) {
|
|
dev_err(xpc_part, "could not setup our reserved page\n");
|
|
|
|
free_irq(SGI_XPC_ACTIVATE, NULL);
|
|
xpc_restrict_IPI_ops();
|
|
|
|
if (xpc_sysctl) {
|
|
unregister_sysctl_table(xpc_sysctl);
|
|
}
|
|
|
|
kfree(xpc_remote_copy_buffer_base);
|
|
return -EBUSY;
|
|
}
|
|
|
|
|
|
/* add ourselves to the reboot_notifier_list */
|
|
ret = register_reboot_notifier(&xpc_reboot_notifier);
|
|
if (ret != 0) {
|
|
dev_warn(xpc_part, "can't register reboot notifier\n");
|
|
}
|
|
|
|
/* add ourselves to the die_notifier list (i.e., ia64die_chain) */
|
|
ret = register_die_notifier(&xpc_die_notifier);
|
|
if (ret != 0) {
|
|
dev_warn(xpc_part, "can't register die notifier\n");
|
|
}
|
|
|
|
|
|
/*
|
|
* Set the beating to other partitions into motion. This is
|
|
* the last requirement for other partitions' discovery to
|
|
* initiate communications with us.
|
|
*/
|
|
init_timer(&xpc_hb_timer);
|
|
xpc_hb_timer.function = xpc_hb_beater;
|
|
xpc_hb_beater(0);
|
|
|
|
|
|
/*
|
|
* The real work-horse behind xpc. This processes incoming
|
|
* interrupts and monitors remote heartbeats.
|
|
*/
|
|
pid = kernel_thread(xpc_hb_checker, NULL, 0);
|
|
if (pid < 0) {
|
|
dev_err(xpc_part, "failed while forking hb check thread\n");
|
|
|
|
/* indicate to others that our reserved page is uninitialized */
|
|
xpc_rsvd_page->vars_pa = 0;
|
|
|
|
/* take ourselves off of the reboot_notifier_list */
|
|
(void) unregister_reboot_notifier(&xpc_reboot_notifier);
|
|
|
|
/* take ourselves off of the die_notifier list */
|
|
(void) unregister_die_notifier(&xpc_die_notifier);
|
|
|
|
del_timer_sync(&xpc_hb_timer);
|
|
free_irq(SGI_XPC_ACTIVATE, NULL);
|
|
xpc_restrict_IPI_ops();
|
|
|
|
if (xpc_sysctl) {
|
|
unregister_sysctl_table(xpc_sysctl);
|
|
}
|
|
|
|
kfree(xpc_remote_copy_buffer_base);
|
|
return -EBUSY;
|
|
}
|
|
|
|
|
|
/*
|
|
* Startup a thread that will attempt to discover other partitions to
|
|
* activate based on info provided by SAL. This new thread is short
|
|
* lived and will exit once discovery is complete.
|
|
*/
|
|
pid = kernel_thread(xpc_initiate_discovery, NULL, 0);
|
|
if (pid < 0) {
|
|
dev_err(xpc_part, "failed while forking discovery thread\n");
|
|
|
|
/* mark this new thread as a non-starter */
|
|
complete(&xpc_discovery_exited);
|
|
|
|
xpc_do_exit(xpcUnloading);
|
|
return -EBUSY;
|
|
}
|
|
|
|
|
|
/* set the interface to point at XPC's functions */
|
|
xpc_set_interface(xpc_initiate_connect, xpc_initiate_disconnect,
|
|
xpc_initiate_allocate, xpc_initiate_send,
|
|
xpc_initiate_send_notify, xpc_initiate_received,
|
|
xpc_initiate_partid_to_nasids);
|
|
|
|
return 0;
|
|
}
|
|
module_init(xpc_init);
|
|
|
|
|
|
void __exit
|
|
xpc_exit(void)
|
|
{
|
|
xpc_do_exit(xpcUnloading);
|
|
}
|
|
module_exit(xpc_exit);
|
|
|
|
|
|
MODULE_AUTHOR("Silicon Graphics, Inc.");
|
|
MODULE_DESCRIPTION("Cross Partition Communication (XPC) support");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_param(xpc_hb_interval, int, 0);
|
|
MODULE_PARM_DESC(xpc_hb_interval, "Number of seconds between "
|
|
"heartbeat increments.");
|
|
|
|
module_param(xpc_hb_check_interval, int, 0);
|
|
MODULE_PARM_DESC(xpc_hb_check_interval, "Number of seconds between "
|
|
"heartbeat checks.");
|
|
|
|
module_param(xpc_disengage_request_timelimit, int, 0);
|
|
MODULE_PARM_DESC(xpc_disengage_request_timelimit, "Number of seconds to wait "
|
|
"for disengage request to complete.");
|
|
|
|
module_param(xpc_kdebug_ignore, int, 0);
|
|
MODULE_PARM_DESC(xpc_kdebug_ignore, "Should lack of heartbeat be ignored by "
|
|
"other partitions when dropping into kdebug.");
|
|
|